Publications on Databases and Information Systems

Peng Yew Chow and Guido Governatori.
Representing and reasoning on XForms document. In Klaus-Dieter Schewe and Hugh E. Williams, editors, Database Technology 2004, number 27 in Conference Research and Practice of Information Technology, pages 141-150. Australian Computer Science Association, ACS, 19-21 January 2004. Copyright © 2004 ACS.
Abstract:Forms are the most common way to interface users and Web-based applications. Traditional forms cannot provide the functionality needed to fulfil the requirements of complex applications. As such, there is a need for a more advanced format of forms to support Web-based application. We argued that XForms easily fit into this criterion of forms. In addition, we observed that there is a need for a tool to reason about the forms with respect to user needs and application requirements. We propose to use Description Logic ALCQI to reason about forms generated by XForms.
 
Guido Governatori and Renato Iannella.
A modelling and reasoning framework for social networks policies. Enterprise Information Systems, 2010 Copyrigth © 2010 Taylor & Francis.
Abstract: Policy languages (such as privacy and rights) have had little impact on the wider community. Now that Social Networks have taken off, the need to revisit Policy languages and realign them towards Social Networks requirements has become more apparent. One such language is explored as to its applicability to the Social Networks masses. We also argue that policy languages alone are not sufficient and thus they should be paired with reasoning mechanisms to provide precise and unambiguous execution models of the policies. To this end we propose a computationally oriented model to represent, reason with and execute policies for Social Networks.
 
Guido Governatori, Antonino Rotolo, and Shazia Sadiq.
A model of dynamic resource allocation in workflow systems. In Klaus-Dieter Schewe and Hugh E. Williams, editors, Database Technology 2004, number 27 in Conference Research and Practice of Information Technology, pages 197-206. Australian Computer Science Association, ACS, 19-21 January 2004, Copyright © 2004 ACS.
Abstract:Current collaborative work environments are characterized by dynamically changing organizational structures. Although there have been several efforts to refine work distribution, especially in workflow management, most literature assumes a static database approach which captures organizational roles, groups and hierarchies and implements a dynamic roles based agent assignment protocol. However, in practice only partial information may be available for organizational models, and in turn a large number of exceptions may emerge at the time of work assignment. In this paper we present an organizational model based on a policy based normative system. The model is based on a combination of an intensional logic of agency and a flexible, but computationally feasible, non-monotonic formalism (Defeasible Logic). Although this paper focuses on the model specification, the proposed approach to modelling agent societies provides a means of reasoning with partial and unpredictable information as is typical of organizational agents in workflow systems.
 
Benjamin Johnston and Guido Goverantori.
An algorithm for the induction of defeasible logic theories from databases. In Klaus-Dieter Schewe and Xiaofang Zhou, editors, Database Technology 2003, number 17 in Conference Research and Practice of Information Technology, pages 75-83. Australian Computer Science Association, ACS, 4-7 February 2003. Copyright © 2003 ACS.
Abstract:Defeasible logic is a non-monotonic logic with applications in rule-based domains such as law. To ease the development and improve the accuracy of expert systems based on defeasible logic, it is desirable to automatically induce a theory of the logic from a training set of precedent data. Empirical evidence suggests that minimal theories that describe the training set tend to be more faithful representations of reality. We show via transformation from the hitting set problem that this global minimization problem is intractable, belonging to the class of NP optimisation problems. Given the inherent difficulty of finding the optimal solution, we instead use heuristics and demonstrate that a best-first, greedy, branch and bound algorithm can be used to find good theories in short time. This approach displays significant improvements in both accuracy and theory size as compared to recent work in the area that post-processed the output of an Aprori association rule-mining algorithm, with comparable execution times.
 
Benjamin Johnston and Guido Governatori.
Induction of defeasible logic theories in the legal domain. In Giovanni Sartor, editor, Procedings of the 9th International Conference on Artificial Intelligence and Law, pages 204-213. IAAIL, ACM Press, 2003.Copyright © 2003 ACM.
Abstract:The market for intelligent legal information systems remains relatively untapped and while this might be interpreted as an indication that it is simply impossible to produce a system that satisfies the needs of the legal community, an analysis of previous attempts at producing such systems reveals a common set of deficiencies that in-part explain why there have been no overwhelming successes to date. Defeasible logic, a logic with proven successes at representing legal knowledge, seems to overcome many of these deficiencies and is a promising approach to representing legal knowledge. Unfortunately, an immediate application of technology to the challenges in this domain is an expensive and computationally intractable problem. So, in light of the benefits, we seek to find a practical algorithm that uses heuristics to discover an approximate solution. As an outcome of this work, we have developed an algorithm that integrates defeasible logic into a decision support system by automatically deriving its knowledge from databases of precedents. Experiments with the new algorithm are very promising - delivering results comparable to and exceeding other approaches.
 
Aqueo Kamada, Guido Governatori, and Shazia Sadiq.
Transformation of SBVR compliant business rules to executable FCL rules. In Mike Dean, John Hall, Antonino Rotolo, and Said Tabet, editors, RuleML 2010: 4th International Web Rule Symposium, number 6403 in LNCS, pages 151-159, Berlin, 2010. Springer. © 2010 Springer.
Abstract: The main source of changing requirements of the dynamic business environment is response to changes in regulations and contracts towards which businesses are obligated to comply. At the same time, many organizations have their business processes specified independently of their business obligations (which include adherence to contracts laws and regulations). Thus, the problem of mapping business changes into computational systems becomes much more complicated. In this paper we address the problem by providing an automated transformation of business rules into a formal language capable of directly mapping onto executable specifications. The model transformation is consistent with MDA/MOF/QVT concepts using ATL to perform the mapping. Business rules are compliant to SBVR metamodel, and are transformed into FCL, a logic based formalism, known to have a direct mapping onto executable specifications. Both, source and target rules are based on principles of deontic logic, the core of which are obligations, permissions and prohibitions.
 
Aqueo Kamada, Guido Governatori, and Shazia Sadiq.
SBVR based business contract and business rule IDE. In Monica Palmirani, Omair Shafiq, Enrico Francesconi, and Fabio Vitali, editors, Proceedings of the RuleML-2010 Challenge, at the 4th International Web Rule Symposium, number 649 in CEUR Workshop Proceedings, pages 8.1-8.8, 2010.
Abstract: We propose an IDE – Integrated Development Environment to model SBVR (Semantic of Business Vocabulary and Business Rule) compliant business rules [2] extracted from business contract of services and store them in an ontological structure of rules, facts and terms as defined in the SBVR metamodel. Business rules are based on principles of deontic logic for treating expressions in the form of normative policies. Deontic constraints express what parties to the contract are required to perform (obligations), what they are allowed to do (permissions), or what they are not allowed to do (prohibitions).
 
Ruopeng Lu, Shazia Sadiq, and Guido Governatori.
Measurement of compliance distance in business processes. Information Systems Management, 25 no. 4 pp. 344-355, 2008., Copyright © 2008 Taylor & Francis.
Abstract: Ensuring that work practice is compliant to regulations and industrial standards is an increasingly important issue in business systems. Whereas as an understanding of control objectives that stem from various legislative, standard and contractual sources may be found at strategic or tactical levels, an assessment of their effective adoption in operational practices is extremely hard. In this paper, we propose a method for assessing the level of compliance in business work practice. The method builds upon business process management platforms, and provides the ability to objectively measure the compliance distance of existing processes within the organization. This in turn empowers process designers and business analysts to quantify the effort required to achieve a compliant process.
 
Ruopeng Lu, Shazia Sadiq, and Guido Governatori.
On managing business processes variants. Data and Knowledge Engineering, 2009.
Abstract: Variance in business process execution can be the result of several situations, such as disconnection between documented models and business operations, workarounds in spite of process execution engines, dynamic change and exception handling, flexible and ad-hoc requirements, and collaborative and/or knowledge intensive work. It is imperative that effective support for managing process variances be extended to organizations mature in their BPM (Business Process Management) uptake so that they can ensure organization wide consistency, promote reuse and capitalize on their BPM investments. This paper presents an approach for managing business processes that is conducive to dynamic change and the need for flexibility in execution. The approach is based on the notion of process constraints. It further provides a technique for effective utilization of the adaptations manifested in process variants. In particular, we will present a facility for discovery of preferred variants through effective search and retrieval based on the notion of process similarity, where multiple aspects of the process variants are compared according to specific query requirements. The advantage of this approach is the ability to provide a quantitative measure for the similarity between process variants, which further facilitates various BPM activities such as process reuse, analysis and discovery.
 
Ruopeng Lu, Shazia Sadiq and Guido Governatori.
Utilizing Successful Work Practice for Business Process Evolution. In Witold Abramowicz and Heinrich C. Mayr editors, Business Information Systems (BIS 2006), volume 85 in \Lecture Notes in Informatics, pages 58-76, Berlin, 2006. Copyright © 2006, GI.
Abstract: Business process management (BPM) has emerged as a dominant technology in current enterprise systems and business solutions. However, business processes are always evolving in current dynamic business environments where requirements and goals are constantly changing. Whereas literature reports on the importance of domain experts in process modelling and adaptations, current solutions have not addressed this issue effectively. In this paper, we present a framework that utilizes successful work practice to support business process evolution. The framework on one hand provides the ability to use domain expert knowledge and experience to tailor individual process instances according to case specific requirements; and on the other, provides a means of using this knowledge through learning techniques to guide subsequent process changes.
 
Ruopeng Lu, Shazia Sadiq, Guido Governatori, and Xiaoping Yang.
Defining adaptation constraints for business process variants. In 12th International Conference on Business Information Systems, Lecture Notes in Business Information Processing 7. Springer, 2009, Copyright © 2009 Springer.
Abstract: In current dynamic business environment, it has been argued that certain characteristics of ad-hocism in business processes are desirable. Such business processes typically have a very large number of instances, where design decisions for each process instance may be made at runtime. In these cases, predictability and repetitiveness cannot be counted upon, as the complete process knowledge used to define the process model only becomes available at the time after a specific process instance has been instantiated. The basic premise is that for a class of business processes it is possible to specify a small number of essential constraints at design time, but allow for a large number of execution possibilities at runtime. The objective of this paper is to conceptualise a set of constraints for process adaptation at instance level. Based on a comprehensive modelling framework, business requirements can be transformed to a set of minimal constraints, and the support for specification of process constraints and techniques to ensure constraint quality are developed.
 
Ruopeng Lu, Shazia Sadiq, and Guido Governatori.
Measurement of compliance distance in business processes. Information Systems Management, 25(4): 344-355, 2008. Copyright © 2008 Taylor & Francis.
Abstract: Ensuring that work practice is compliant to regulations and industrial standards is an increasingly important issue in business systems. Whereas as an understanding of control objectives that stem from various legislative, standard and contractual sources may be found at strategic or tactical levels, an assessment of their effective adoption in operational practices is extremely hard. In this paper, we propose a method for assessing the level of compliance in business work practice. The method builds upon business process management platforms, and provides the ability to objectively measure the compliance distance of existing processes within the organization. This in turn empowers process designers and business analysts to quantify the effort required to achieve a compliant process.
 
Ruopeng Lu, Shazia Sadiq, Vineet Padmanabhan and Guido Governatori.
Using a Temporal Constraint Network for Business Process Execution. In Gillian Dobbie and James Bailey, editors, Database Technology 2006, number 49 in Conference Research and Practice of Information Technology, pages 157-166. Australian Computer Science Association, ACS, 16-19 January 2006. Copyright © 2006 ACS.
Abstract: Business process management (BPM) has emerged as a dominant technology in current enterprise systems and business solutions. However, the technology continues to face challenges in coping with dynamic business environments where requirements and goals are constantly changing. In this paper, we present a modelling framework for business processes that is conducive to dynamic change and the need for flexibility in execution. This framework is based on the notion of process constraints. Process constraints may be specified for any aspect of the process, such as task selection, control flow, resource allocation, etc. Our focus in this paper is on a set of scheduling constraints that are specified through a temporal constraint network. We will demonstrate how this specification can lead to increased flexibility in process execution, while maintaining a desired level of control. A key feature and strength of the approach is to use the power of constraints, while still preserving the intuition and visual appeal of graphical languages for process modelling.
 
Vineet Padmanabhan, Guido Governatori, Shazia Sadiq, Robert Colomb and Antonino Rotolo.
Process Modelling: The Deontic Way. In Markus Stumptner, Sven Hartmann and Yasushi Kiyoki, editors, Database Technology 2006, number 53 in Conference Research and Practice of Information Technology, pages 75-84. Australian Computer Science Association, ACS, 16-19 January 2006. Copyright © 2006 ACS.
Abstract:Current enterprise systems rely heavily on the modelling and enactment of business processes. One of the key criteria for a business process is to represent not just the behaviours of the participants but also how the contractual relationships among them evolve over the course of an interaction. In this paper we provide a framework in which one can define policies/ business rules using deontic assignments to represent the contractual relationships. To achieve this end we use a combination of deontic/normative concepts like proclamation, directed obligation and direct action to account for a deontic theory of commitment which in turn can be used to model business processes in their organisational settings. In this way we view a business process as a social interaction process for the purpose of doing business. Further, we show how to extend the i* framework, a well known organisational modelling technique, so as to accommodate our notion of deontic dependency.
 
Monica Palmirani, Guido Governatori, and Giuseppe Contissa.
Temporal dimensions in rules modelling. In Radboud Winkels, editor, Legal Knowledge and Information Systems JURIX 2010: The Twenty-Third Annual Conference, Frontiers in Artificial Intelligence and Applications, Amsterdam, 2010. IOS Press.
Abstract: Typically legal reasoning involves multiple temporal dimensions. The contribution of this work is to extend LKIF-rules (LKIF is a proposed mark-up language designed for legal documents and legal knowledge in ESTRELLA Project [3]) with temporal dimensions. We propose an XML-schema to model the various aspects of the temporal dimensions in legal domain, and we discuss the design choices. We illustrate the use of the temporal dimensions in rules with the help of real life examples.
 
Pakornpong Pothipruk and Guido Governatori
A Formal Ontology Reasoning with Individual Optimization: A Realization of the Semantic Web. In M. Kitsuregawa, E. Neuhold and A. Ngu, editors, Web Information Systems Engineering. WISE 2005, pages 119-134. LNCS 3806, Springer, Berlin, 2005, The original pubblication is available at www.springerlink.com.
Abstract: Answering a query over a group of RDF data pages is a trivial process. However, in the Semantic Web, there is a need for ontology technology. Consequently, OWL, a family of web ontology languages based on description logic, has been proposed for the Semantic Web. Answering a query over the Semantic Web is thus not trivial, but a deductive process. However, the reasoning on OWL with data has an efficiency problem. Thus, we introduce optimization techniques for the inference algorithm. This work demonstrates the techniques for instance checking and instance retrieval problems with respect to $\mathcal{ALC}$ description logic which covers certain parts of OWL.
 
Pakornpong Pothipruk and Guido Governatori.
An Optimization for Query Answering on ALC Database. In Gillian Dobbie and James Bailey, editors, Database Technology 2006, number 49 in Conference Research and Practice of Information Technology, page 129-137. Australian Computer Science Association, ACS, 16-19 January 2006. Copyright © 2006 ACS.
Abstract: Query answering over OWLs and RDFs on the Semantic Web is, in general, a deductive process. To this end, OWL, a family of web ontology languages based on description logic, has been proposed as the language for the Semantic Web. However, reasoning even on ALC, a description logic weaker than OWL, faces efficiency problem. To obviate this problem, at least for ALC, we propose a partition approach that improves the efficiency by splitting the search space into independent Aboxes. Each partition class, i.e., an Abox, can be queried independently. The answer to a query is the simple combination of the answers from each Abox. We prove the correctness of this approach and we outline how to represent compactly the content of each independent Abox. This work can be seen as an optimization for querying a deductive semi-structured database.
 
Bela Stantic, Guido Governatori and Abdul Sattar.
Handling of Current Time in Native XML Databases. In Gillian Dobbie and James Bailey, editors, Database Technology 2006, number 49 in Conference Research and Practice of Information Technology, 175-182. Australian Computer Science Association, ACS, 16-19 January 2006. Copyright © 2006 ACS.
Abstract:The introduction of Native XML databases opens many research questions related to the data models used to represent and manipulate data, including temporal data in XML. Increasing use of XML for Valid Web pages warrants an adequate treatment of now in Native XML databases. In this study, we examined how to represent and manipulate now-relative temporal data. We identify different approaches being used to represent current time in XML temporal databases, and introduce the notion of storing variables such as `now' or `UC' as strings in XML native databases. All approaches are empirically evaluated on a query that time-slices the timeline at the current time. The experimental results indicate that the proposed extension offers several advantages over other approaches: better semantics, less storage space and better response time.
 
Bela Stantic, Paolo Terenziani, Abdul Sattar, Alessio Bottrighi, and Guido Governatori.
Towards an implicit treatment of periodically-repeated medical data. In Charles Safran, Shane Reti, and Heimar Marin, editors, MEDINFO 2010. Proceedings of the 13th World Congress on Medical Informatics, pages1131-1135. Volume 160 of Studies in Health Technology and Informatics, Amsterdam, 2010. IOS Press, Copyrigth © 2010 IMIA and SAHIA.
Abstract: Temporal information plays a crucial role in medicine, so that in Medical Informatics there is an increasing awareness that suitable database approaches are needed to store and support it. Specifically, a great amount of clinical data (e.g., therapeutic data) are periodically repeated. Although an explicit treatment is possible in most cases, it causes severe storage and disk I/O problems. In this paper, we propose an innovative approach to cope with periodic medical data in an implicit way. We propose a new data model, representing periodic data in a compact (implicit) way, which is a consistent extension of TSQL2 consensus approach. Then, we identify some important types of temporal queries, and present query answering algorithms to answer them. We also sketch a temporal relational algebra for our approach. Finally, we show experimentally that our approach outperforms current explicit approaches.
 
Insu Song and Guido Governatori.
Affective web service design. In Qiang Yang and Geoff Webb, editors, Ninth Pacific Rim International Conference on Artificial Intelligence, LNAI 4099, pages 71-80, Guilin, 7-11 August 2006. Springer, Copyright © 2006 Springer.
Abstract:In this paper, we propose that, in order to improve customer satisfaction, we need to incorporate communication modes (e.g., speech act) in the current standards of web services specifications. We show that with the communication modes, we can estimate various affects on service consumers during their interactions with web services. With this information, a web-service management system can automatically prevent and compensate potential negative affects, and even take advantage of positive affect.